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Title: Image Artifacts Resulting from Gamma-Ray Tracking Algorithms Used with Compton Imagers

Abstract

For Compton imaging it is necessary to determine the sequence of gamma-ray interactions in a single detector or array of detectors. This can be done by time-of-flight measurements if the interactions are sufficiently far apart. However, in small detectors the time between interactions can be too small to measure, and other means of gamma-ray sequencing must be used. In this work, several popular sequencing algorithms are reviewed for sequences with two observed events and three or more observed events in the detector. These algorithms can result in poor imaging resolution and introduce artifacts in the backprojection images. The effects of gamma-ray tracking algorithms on Compton imaging are explored in the context of the 4π Compton imager built by the University of Michigan.

Authors:
;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
877013
Report Number(s):
PNNL-SA-42860
TRN: US0601532
DOE Contract Number:
AC05-76RL01830
Resource Type:
Conference
Resource Relation:
Conference: 2004 IEEE Nuclear Science Symposium Conference Record, 1599-1603
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; ALGORITHMS; RESOLUTION; COMPTON EFFECT; IMAGES; GAMMA DETECTION; RADIATION DETECTORS; gamma-ray imaging; Compton imaging; gamma-ray tracking; image reconstruction

Citation Formats

Seifert, Carolyn E., and He, Zhong. Image Artifacts Resulting from Gamma-Ray Tracking Algorithms Used with Compton Imagers. United States: N. p., 2005. Web.
Seifert, Carolyn E., & He, Zhong. Image Artifacts Resulting from Gamma-Ray Tracking Algorithms Used with Compton Imagers. United States.
Seifert, Carolyn E., and He, Zhong. Sat . "Image Artifacts Resulting from Gamma-Ray Tracking Algorithms Used with Compton Imagers". United States. doi:.
@article{osti_877013,
title = {Image Artifacts Resulting from Gamma-Ray Tracking Algorithms Used with Compton Imagers},
author = {Seifert, Carolyn E. and He, Zhong},
abstractNote = {For Compton imaging it is necessary to determine the sequence of gamma-ray interactions in a single detector or array of detectors. This can be done by time-of-flight measurements if the interactions are sufficiently far apart. However, in small detectors the time between interactions can be too small to measure, and other means of gamma-ray sequencing must be used. In this work, several popular sequencing algorithms are reviewed for sequences with two observed events and three or more observed events in the detector. These algorithms can result in poor imaging resolution and introduce artifacts in the backprojection images. The effects of gamma-ray tracking algorithms on Compton imaging are explored in the context of the 4π Compton imager built by the University of Michigan.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sat Oct 01 00:00:00 EDT 2005},
month = {Sat Oct 01 00:00:00 EDT 2005}
}

Conference:
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